title: Phosphorylation of kinesin light chain 1 at serine 460 modulates binding and trafficking of calsyntenin-1.
abstract: Kinesin light chain 1 (KLC1) binds to the intracellular cytoplasmic domain of the type-1 membrane-spanning protein calsyntenin-1 (also known as alcadein-α) to mediate transport of a subset of vesicles. Here, we identify serine 460 in KLC1 (KLC1ser460) as a phosphorylation site and show that mutation of KLC1ser460 influences the binding of KLC1 to calsyntenin-1. Mutation of KLC1ser460 to an alanine residue, to preclude phosphorylation, increased the binding of calsyntenin-1, whereas mutation to an aspartate residue, to mimic permanent phosphorylation, reduced the binding. Mutation of KLC1ser460 did not affect the interaction of KLC1 with four other known binding partners: huntingtin-associated protein 1 isoform A (HAP1A), collapsin response mediator protein-2 (CRMP2), c-Jun N-terminal kinase-interacting protein-1 (JIP1) and kinase-D-interacting substrate of 220 kDa (Kidins220). KLC1ser460 is a predicted mitogen-activated protein kinase (MAPK) target site, and we show that extracellular-signal-regulated kinase (ERK) phosphorylates this residue in vitro. We also demonstrate that inhibition of ERK promotes binding of calsyntenin-1 to KLC1. Finally, we show that expression of the KLC1ser460 mutant proteins influences calsyntenin-1 distribution and transport in cultured cells. Thus, phosphorylation of KLC1ser460 represents a mechanism for selectively regulating the binding and trafficking of calsyntenin-1.
authors.affiliation: MRC Centre for Neurodegeneration Research, Institute of Psychiatry, King's College London, PO Box 37, De Crespigny Park, Denmark Hill, London SE5 8AF, UK.
authors.forename: Alessio
authors.initials: A
authors.lastname: Vagnoni
authors.forename: Lilia
authors.initials: L
authors.lastname: Rodriguez
authors.forename: Catherine
authors.initials: C
authors.lastname: Manser
authors.forename: Kurt J
authors.initials: KJ
authors.lastname: De Vos
authors.forename: Christopher C J
authors.initials: CC
authors.lastname: Miller
mesh_terms: D020816:Amino Acid Motifs; D019943:Amino Acid Substitution; D000818:Animals; D016466:CHO Cells; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D006224:Cricetinae; D003412:Cricetulus; D006801:Humans; D016547:Kinesins; D008869:Microtubule-Associated Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D011485:Protein Binding; D021381:Protein Transport
chemical_list: C503225:CLSTN1 protein, human; D002135:Calcium-Binding Proteins; C503227:Clstn1 protein, mouse; C000715688:KLC1 protein, human; C000715695:Kns2 protein, mouse; D008869:Microtubule-Associated Proteins; D016547:Kinesins